Method of assembly of articles

ABSTRACT

An assembly method for first and second articles is disclosed. A first substrate with a plurality of first articles and a second substrate with a plurality of second articles are selected. The articles on the flexible substrate webs with different pitches are assembled together by displacing portions between the first articles of one web out of plane to move the first articles on that web to the same shorter pitch as the second articles on the other web, aligning the two webs to register corresponding first and second articles on the two webs, and assembling the corresponding articles together. The assembly may be used for example in the making of RFID tags, labels and inlays.

TECHNICAL FIELD OF THE INVENTION

This disclosure relates to methods for high-speed assembly of articlesarranged in linear arrays, and in particular to articles arranged inlinear arrays that have different dimensions and/or pitch.

BACKGROUND OF THE INVENTION

Automatic identification of products has become commonplace. Forexample, the ubiquitous barcode label, placed on food, clothing, andother objects, is currently the most widespread automatic identificationtechnology that is used to provide merchants, retailers and shipperswith information associated with each object or item of merchandise.

Another technology used for automatic identification products is RadioFrequency Identification (RFID). RFID uses labels or “tags” that includeelectronic components that respond to radio frequency commands andsignals to provide identification of each tag wirelessly. Generally,RFID tags and labels comprise an integrated circuit (IC, or chip)attached to an antenna that responds to a reader using radio waves tostore and access the information in the chip. Specifically, RFID tagsand labels have a combination of antennas and analog and/or digitalelectronics, which often includes communications electronics, datamemory, and control logic.

One of the obstacles to more widespread adoption of RFID technology isthat the cost of RFID tags are still relatively high as lower costcomponents and optimization of economical manufacturing of RFID tags hasnot been achievable using current production methods. Additionally, asthe demand for RFID tags has increased the pressure has also increasedfor manufacturers to reduce the cost of the tags, as well as to reducethe size of the electronics as much as possible so as to: (1) increasethe yield of the number of chips (dies) that may be produced from asemiconductor wafer, (2) reduce the potential for damage, as the finaldevice size is smaller, and (3) increase the amount of flexibility indeployment, as the reduced amount of space needed to provide the samefunctionality may be used to provide more capability.

However, as the chips become smaller, their interconnection with otherdevice components, e.g., antennas, becomes more difficult. Thus, tointerconnect the relatively small contact pads on the chips to theantennas, intermediate structures variously referred to as “straps,”“interposers,” and “carriers” are sometimes used to facilitate inlaymanufacture. Interposers include conductive leads or pads that areelectrically coupled to the contact pads of the chips for coupling tothe antennas. These leads provide a larger effective electrical contactarea between the chips and the antenna than do the contact pads of thechip alone. Otherwise, an antenna and a chip would have to be moreprecisely aligned with each other for direct placement of the chip onthe antenna without the use of such strap. The larger contact areaprovided by the strap reduces the accuracy required for placement of thechips during manufacture while still providing effective electricalconnection between the chip and the antenna. However, the accurateplacement and mounting of the dies on straps and interposers stillprovide serious obstacles for high speed manufacturing of RFID tags andlabels.

One such challenging area arises from the fact that the various elementsthat are assembled to form a complete RFID device are provided arrangedon linear arrays such as on a tape or web. The two webs are unwound atmatched speeds so that each pair of articles to be assembled reach theassembly point at the same instant, where they are assembled together(e.g. via application of heat, pressure, adhesives, solder, mechanicalfasteners, any combination of the foregoing, etc.) For purposes ofincreasing efficiency, the pitch of these articles (i.e. spacing betweenthem) on the substrate is typically as close as practicable. In the caseof antennas and straps, however, because of their different physicalsize and their respective manufacturing processes as well as subsequentassembly steps for the final product, the pitch of the arrays of theantennas and of the straps on their respective substrates is different.Thus registering (i.e. matching) a strap array with an antenna array isa rather difficult task. Current solutions to this problem includecutting each individual strap and accelerating it to meet the respectiveantenna at the point of assembly, or unwinding the two webs at differentspeeds. As those skilled in the art will appreciate, both of thesesolutions require sophisticated equipment and are prone to encounterproblems as the assembly speed is increased.

What is therefore needed are simpler and more economical methods anddevices for assembling together articles that are delivered in lineararrays arranged on substrates at different pitches, and which willsupport high speed assembly of the articles. The embodiments of thepresent disclosure answer these and other needs.

BRIEF SUMMARY OF THE INVENTION

The embodiments of the present invention described below are notintended to be exhaustive or to limit the invention to the precise formsdisclosed in the following detailed description. Rather, the embodimentsare chosen and described so that others skilled in the art mayappreciate and understand the principles and practices of the presentinvention.

The present invention is directed to a process for optimization of RFIDmanufacture by displacing material web length of one web in order toquickly assemble components from a second web to create an intermediateassembly which can be used to form a finished product.

In a first embodiment disclosed herein, an assembly method comprisesselecting a first flexible planar substrate with a plurality of firstarticles disposed in a linear array thereon with a first spacing betweenadjacent first articles; selecting a second planar substrate with aplurality of second articles disposed in a linear array thereon with asecond spacing between adjacent second articles that is shorter than thefirst spacing; displacing portions of the first substrate betweenadjacent first elements out of the plane of the first substrate tothereby draw adjacent first elements closer to one another; aligning thefirst and second substrates so that each first article is disposed insuccession adjacent a corresponding second article in succession; andassembling each first article to the corresponding second article.Displacing portions of the first substrate between adjacent firstelements out of the plane of the first substrate may be accomplished byapplying negative pressure to portions of the first substrate in orderto draw out portions of the plane. In another embodiment, theapplication of positive pressure can be used to displace portions of thefirst substrate between adjacent first elements out of the plane of thefirst substrate. Positive pressure may comprise applying a mechanicalforce to portions of the first substrate to impel portions out of theplane.

In another embodiment disclosed herein, an assembly method comprisesbending a web between first components out of plane until the firstcomponents match the pitch of second components on another web andattaching the first components to corresponding second components.

In a still further exemplary embodiment of the presently describedinvention, an intermediate assembly is provided and includes a first webhaving a plurality of first elements spaced apart a first distance. Asecond web is provided that has a plurality of second elements distinctfrom the first element and spaced apart from one another a seconddistance different than the first distance. The second web is displacedfrom a machine direction to a second direction substantiallyperpendicular to the machine direction. The first web is disposed overthe second web such that the first elements are juxtaposed over thesecond elements in a one to one relationship.[0013] These and otherfeatures and advantages will become further apparent from the detaileddescription and accompanying figures that follow. In the figures anddescription, numerals indicate the various features, like numeralsreferring to like features throughout both the drawings and thedescription.

BRIEF DESCRIPTION OF THE DRAWINGS

These, as well as other objects and advantages of this invention, willbe more completely understood and appreciated by referring to thefollowing more detailed description of the presently preferred exemplaryembodiments of the invention in conjunction with the accompanyingdrawings, of which:

FIG. 1( a)-(b) is a schematic front view of webs with articles as may beutilized with the method of the present disclosure;

FIG. 2( a)-(b) is a side view of one the webs with articles of FIG. 1before and after processed by the method of the present disclosure;

FIG. 3( a)-(b) is a side view of the webs with articles of FIG. 1 beingassembled in accordance with the method of the present disclosure; and

FIG. 4( a)-(b) illustrate different embodiments of practicing the methodof the present disclosure; and

FIG. 5 provides a block diagram for an exemplary assembly method forhigh speed assembly of articles arranged in linear arrays that havedifferent dimensions and/or pitch.

DETAILED DESCRIPTION

Referring to FIG. 1, a typical web 100 with antenna elements 110 forRFID devices is illustrated in FIG. 1( a), and a typical web 120 with,e.g., straps 130 is illustrated in FIG. 1( b). As clearly shown, and asdiscussed previously, the antennas 110 and straps 130 are spaced with adifferent pitch on their respective webs 100, 120. In accordance withthe present disclosure, in order to match every single strap 130 on theweb in order with a corresponding antenna 110, the web with the greaterpitch between the articles disposed thereon—is intermittently displacedalong its length and out of its normal plane or direction of machinetravel such that the antenna elements disposed thereon are broughtphysical closer to each other until they are disposed with a pitch therebetween that is sufficiently equal to the pitch of the straps web 120 toallow assembly of antenna-strap pairs. In this exemplary embodiment, theantenna web 100 has the greatest pitch.

This concept is best illustrated in FIG. 2, which depicts a side view ofantenna web 100. If it can be said, for purposes of discussion, that theantenna web lies in a plane defined by x- and y-axes with the antennas110 extending linearly along the x-axis, in a machine direction, thenFIG. 2( a) depicts the antenna web as it extends along the x- andz-axes, looking along the y-axis. As depicted in FIG. 2( b), inaccordance with the present disclosure, the antenna web 100 is displacedbetween the antenna elements 110 prior to assembly so that the portionsof the antenna web lying between adjacent antenna elements are extendedalong the z-axis, thereby drawing adjacent antenna elements closer toeach other.

As illustrated in FIG. 3( a), displacing the antenna web 100 along thez-axis as described allows matching the pitch of the antenna elements110 to match the pitch of the straps 130 as they are disposed on theundistorted strap web 120. That is, the strap web or first element webremains in the first plane or y axis in a machine direction and portionsare not displaced out of alignment from this plane, the web remains inits machine direction position. This in turn, and as depicted in FIG. 3(b), allows corresponding antennas and straps on the two respective webs100, 120 to be easily and simply registered, contacted (such as withadhesive 310) and optionally heat and/or pressure treated with anappropriate device 320. Additional methods of assembly may includesoldering, and welding, the straps and the antennas to one another.

Displacing the antenna web 100 along the z-axis as disclosed herein maybe accomplished by any practicable means, at least some of which will beimmediately obvious to the skilled person, and the method ofdisplacement is in no way a limit upon the scope of the presentlyclaimed invention. For purposes of illustration only and with referenceto FIG. 4( a), one possible method is to apply a vacuum or suction force400 to the portions of the web lying between adjacent articles disposedthereon, because as known in the art, the webs are typically formed of aflexible material, such as plastic, paper, foils and the like. Inanother illustrative, non-limiting embodiment depicted in FIG. 4( b)(not drawn to scale), a mechanical force such as applied by a toothedwheel 420 may be impinged onto the portions of the web lying betweenadjacent articles disposed thereon to force them to extend (i.e. fold)into the z-axis dimension. Alternatively, a blast of air or gas could beimpinged onto the web, in a method essentially opposite to that of FIG.4( a). In addition, stepper motors, dancer bars and the like may be usedto create the displacement in the web.

Following registering and assembly of each antenna and strap pair, thestrap web 120 may be cut between each strap to thereby allow expandingthe distorted portions of the antenna web 100 and thereby returning theantenna web to a planar configuration for subsequent processing steps.

FIG. 5 illustrates a block diagram of an exemplary method of articlesarranged in linear arrays. A first flexible planar substrate is selectedwith a plurality of first articles disposed in a linear array thereonwith a first spacing between adjacent first articles at step 200. Asecond planar substrate is then selected with a plurality of secondarticles disposed in a linear array thereon with a second spacingbetween adjacent second articles that is shorter than the first spacingat step 210. Third, displacing portions of the first substrate betweenadjacent first elements (e.g. antenna) of the plane of the firstsubstrate to thereby draw adjacent first elements closer to one anotherat step 220. Fourth, the first and second substrates are aligned so thateach first article or element is disposed in succession adjacent acorresponding second article (strap, transponder, chip or secondelement) in succession 230. Lastly, the first article is assembledcorresponding to the second article 240.

It is important to understand that the present invention is not limitedto antenna and strap elements for RFID devices, which were discussed forease of illustration only. Rather, the method of the present inventionmay be applied to any assembly process that entails assembling articlesdisposed on flexible substrates at a different pitch on each respectiveweb. As will be appreciated by the skilled reader, the method of thepresent invention allows the design and use of simpler and thereby morecost effective and robust assembly machines, and higher assembly speeds.In addition, the process of the present invention could also be used inthe assembly of finished RFID tags, such as apparel hang tags andlabels. For example, a web of RFID inlays can have a first pitch and aweb of material to form apparel hang tags has a second pitch. The RFIDinlay web may go through the displacement so as to align with thematerial to form the finished RFID tags.

Having now described the invention in accordance with the requirementsof the patent statutes, those skilled in this art will understand how tomake changes and modifications to the present invention to meet theirspecific requirements or conditions. Such changes and modifications maybe made without departing from the scope and spirit of the invention asdisclosed herein.

The foregoing Detailed Description of exemplary and preferredembodiments is presented for purposes of illustration and disclosure inaccordance with the requirements of the law. It is not intended to beexhaustive nor to limit the invention to the precise form(s) described,but only to enable others skilled in the art to understand how theinvention may be suited for a particular use or implementation. Thepossibility of modifications and variations will be apparent topractitioners skilled in the art. No limitation is intended by thedescription of exemplary embodiments which may have included tolerances,feature dimensions, specific operating conditions, engineeringspecifications, or the like, and which may vary between implementationsor with changes to the state of the art, and no limitation should beimplied therefrom. Applicant has made this disclosure with respect tothe current state of the art, but also contemplates advancements andthat adaptations in the future may take into consideration of thoseadvancements, namely in accordance with the then current state of theart. It is intended that the scope of the invention be defined by theClaims as written and equivalents as applicable. Reference to a claimelement in the singular is not intended to mean “one and only one”unless explicitly so stated. Moreover, no element, component, nor methodor process step in this disclosure is intended to be dedicated to thepublic regardless of whether the element, component, or step isexplicitly recited in the Claims. No claim element herein is to beconstrued under the provisions of 35 U.S.C. Sec. 112, sixth paragraph,unless the element is expressly recited using the phrase “means for . .. ” and no method or process step herein is to be construed under thoseprovisions unless the step, or steps, are expressly recited using thephrase “comprising the step(s) of . . . . ”

What is claimed is:
 1. An assembly method, comprising: selecting a firstflexible planar substrate with a plurality of first articles disposed ina linear array thereon with a first spacing between adjacent firstarticles; selecting a second planar substrate with a plurality of secondarticles disposed in a linear array thereon with a second spacingbetween adjacent second articles that is shorter than the first spacing;displacing portions of the first substrate between adjacent firstarticles out of the plane of the first substrate to thereby drawadjacent first articles closer to one another; aligning the first andsecond substrates so that each first article is disposed in successionadjacent a corresponding second article in succession; and assemblingeach first article to the corresponding second article.
 2. The method ofclaim 1, wherein the substrate is a plastic, paper, or foil.
 3. Themethod of claim 1, wherein adjacent first elements are drawn to withinthe second spacing from one another.
 4. The method of claim 1, whereindisplacing the portions of the first substrate between adjacent firstelements out of the plane of the first substrate comprises applyingnegative pressure to the portions of the first substrate to draw theportions out of plane.
 5. The method of claim 1, wherein displacing theportions of the first substrate between adjacent first elements out ofthe plane of the first substrate comprises applying positive pressure tothe portions of the first substrate to impel the portions out of plane.6. The method of claim 5, wherein applying positive pressure comprisesapplying a mechanical force to the portions of the first substrate toimpel the portions out of plane.
 7. The method of claim 1, whereindisplacing includes applying a vacuum or suction force.
 8. The method ofclaim 1, wherein the first and second articles are components of an RFIDdevice.
 9. The method of claim 1, wherein the first and second articlesare antenna elements.
 10. The method of claim 1, further comprisingafter assembling the articles: cutting the second substrate betweenadjacent second articles; and releasing the displaced portions of thefirst substrate into the plane of first substrate.
 11. The method ofclaim 1, wherein assembling the articles comprises one selected from thegroup consisting of applying adhesive to at least one of the articles,applying pressure to the articles, applying heat to the articles,soldering the articles, and welding the articles.
 12. The method ofclaim 1, wherein the first articles are RFID inlays and the secondarticles are materials for an apparel hang tag.
 13. The method of claim1, wherein displacing the portions of the first substrate betweenadjacent first elements out of the plane of the first substratecomprises the step of wrapping the first substrate around a toothedwheel.
 14. The method of claim 1, wherein displacing the portions of thefirst substrate between adjacent first elements out of the plane of thefirst substrate comprises force created by a stepper motor or dancerbar.
 15. The method of claim 8, wherein one of the components is a chipor strap.